Samsung will not charge your credit/debit card until your order is being prepared to ship from our warehouse, or is ready to pick up.
When you place your order, a pre-authorization hold for the funds will be put on your card for the total amount, plus all taxes, fees, and shipping charges, if any. This hold allows us to begin processing and fulfilling your order. When your order is getting ready to ship—or is ready for pick-up—the payment will be authorized, and the charge will occur.

Note: Orders placed with PayPal and Amazon Pay are charged immediately after the order is placed.

Want more information about pre-authorization holds after a Samsung purchase? See this article